byteorder: remove direct includes of linux/byteorder/swab[b].h

A consolidated implementation will provide this generically through
asm/byteorder, remove direct includes to avoid breakage when the
changeover to the new implementation occurs.

This hunk was lost from commit 1d8cca44


("byteorder: provide swabb.h generically in asm/byteorder.h")

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>